Clays from this region have glassy spherules with limestone-like chemistry, and another characteristic of this region is the presence of quartz with various criss-cross patterns. Abnormally high concentrations of a transition
Clays from this region have glassy spherules with limestone-like chemistry, and another characteristic of this region is the presence of quartz with various criss-cross patterns. Abnormally high concentrations of a transition element at this region led to a proposition that the Chicxulub Crater was caused by a meteor striking the Earth, and was advanced by Walter and Luis Alvarez. It is thought that the dinosaurs died out at the same time that this rock layer was formed from dust and debris from a meteor about 65.5 million years ago. For 10 points, identify this layer of rocks that mark the distinction between the Cretaceous and Tertiary periods.
Clays from this region have glassy spherules with limestone-like chemistry, and another characteristic of this region is the presence of quartz with various criss-cross patterns.
{K}-{T Boundary} [accept {Cretaceous}-{Tertiary boundary} early; accept {K}-{Pg boundary} or {Cretacious}-{Paleogene boundary}]